EPA Method 515.1 Internal Standard Back Catalog number: 31023 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 673528 2,4'-DDD, 100 µg/ml, Ethyl acetate, 5ml Price on request 2533.11-25MG (2RS)-2-(4-Ethylphenyl)propanoic acid, neat, Solvent-neat, Unit 25mg, # of units-1, Cas.no. 3585-52-2 Price on request 680053 (S)-Equol, 10mg Price on request